Electrical stimulation, or pacing, was advocated as a possible treatment for gastric motor dysfunction as early as 1963. Experimentation in the late 1960s and early 1970s, began to demonstrate the significance of gastrointestinal myoelectrical activity and its relation to contractile activity.
Electrical stimulation has been shown to be able to alter, inhibit, or excite gastrointestinal motor functions, activate intrinsic and extrinsic neuronal pathways and/or solicit hormonal/peptide releases. Because of these characteristics, electrical stimulation has been shown to be effective in normalizing gastric dysrhythmia, accelerating gastric emptying, and reducing symptoms such as nausea and vomiting. Recently, electrical stimulation has also been studied as a therapy for obesity.
Obesity is a growing public health problem with a lack of satisfactory treatments. Recent research seems to suggest that electrical stimulation may delay gastric emptying and thereby assist in prolonging meal intervals and reducing frequent snacking without the risks and complications of surgery. Fluid intake may also be induced by electrical stimulation so as to assist in reducing appetite, for example, by reducing the capacity for accommodating food within the gastrointestinal tract as detailed in “Therapeutic Potential of Duodenal Electrical Stimulation for Obesity: Acute Effects on Gastric Emptying and Water Intake” by Shi Liu, Xiaohua Hou, and J. D. Z. Chen in American Journal of Gastroenterology, Volume 100, pages 792-796 (2005) that is hereby incorporated by reference in its entirety.
Most of the devices developed to provide for electrical stimulation are located within the gastric region of the gastrointestinal tract. See GASTROINTESTINAL PACEMAKER HAVING PHASED MULTIPOINT STIMULATION (U.S. Pat. No. 5,690,691), GASTROINTESTINAL ELECTRICAL STIMULATION (U.S. Pat. No. 6,826,428), SENSOR BASED GASTROINTESTINAL ELECTRICAL STIMULATION FOR THE TREATMENT OF OBESITY OR MOTILITY DISORDERS (U.S. Patent Publication No. 2005/0222638), PROCESS FOR ELECTROSTIMULATION TREATMENT OF MORBID OBESITY (U.S. Pat. Publication No. 2004/0088022), TACHYGASTRIAL ELECTRICAL STIMULATION (U.S. Pat. Publication No. 2005/0222637), each of which is hereby incorporated by reference in its entirety.
The enteric nervous system (ENS) contains numerous short axon and inter-neurons in the intestinal wall. The vast number of neurons and neuronal connections in the intestinal ENS carry out many digestive reflexes independent from the central nervous system. For example, the complex movements of peristalsis seen in the esophagus, stomach, and intestine are entirely initiated and regulated by the ENS. In addition, many neurotransmitters are released by ENS neurons to control glandular secretion and muscle contraction in the gut wall. Research has shown that stimulation in one area of the intestinal tract can provide stimulation in a whole other area within the ENS system.